/Engine/Source/Runtime/Experimental/Chaos/Public/Chaos/Utilities.h
Approximate Asin(X) to 5th order ~= X + (1/6)X^3 + (3/40)X^5 + ... Returns an approximation for all valid input range [-1, 1] with an error that increases as the input magnitude approaches 1.
namespace Chaos { namespace Utilities { template<typename T> T Chaos::Utilities::AsinEst5 ( const T X ) } }